1. Field of the Invention
The present invention relates to a hammer-type stapler with cartridge and more particularly pertains to manually operated impact staplers in building, for striking staples into working piece, for example, thin board, blanket, or asphalt felt on the roof, and fix it.
2. Description of the Prior Art
The use of stapler is known in building. Hammer-type stapler is usually needed in the building site without electric power, like out door.
Known prior art includes U.S. Pat. No. 3,113,117; U.S. Pat. No. 6,012,623.
Two kinds of hammer-type staplers are as follow. Referring to FIG. 1 is a perspective view of the first kind of hammer-type stapler of prior art. By holding the handle 1001 and wielding the stapler to make the driving element guiding device 2001 to strike a target piece. Because of the force of inertia, the driving element 1101 will move in curving line with an axle center of the pin 1002 (referring to FIG. 2). The driving element 1101 will strike the first staple 2002 into the target piece.
However, the driving element 1101 does not strike the staples in a vertical line. It will increase the opportunity of jam (means the staple was jammed in the driving element guiding device 2001) because of the side-direction force. To clean a jam, first, remove the hook set 3002 from the end of the casing 100. Second, take out the press spring set 300, then pull the pin 1002. Lastly, take out the staple containing set 200 from the front portion of the casing 100. After removing the jammed staple, install all the elements in reverse order. It takes so many steps and is very complicated. When installing the elements in reverse order, it is easy to miss an element, especially when working outdoor.
Referring to FIG. 3 is the second kind of hammer-type stapler of prior art. By holding the handle 400 and wielding the ahead striking hammer set 500 to strike a target piece. Because of the reacting force, the trip lever 600 which projected downward will move upward along the guiding groove 6001 of the trip lever 600 and push a control pin 5001. Referring to FIG. 4-5, is a perspective view of the striking hammer set of prior art. Because the control pin 5001 is fixed on the stapler pusher 5003, by applying the principle of lever, the control pin 5001, then, makes the stapler pusher 5003 move counterclockwise with a fulcrum of a rivet 5002. A tip 5004 formed at the front of the stapler pusher 5003 push a driving element 700 downward in a curving way, then the driving element 700 strikes a staple 701 and into a target piece. An elastic plate 5005 push the stapler pusher 5003 to the original position.
The second kind of stapler doesn't move vertically either. On the other hand, if a jam should occur, referring to FIGS. 6A-6D is the perspective view of the jam cleaning procedure of the second kind of prior art. First, as shown in the FIG. 6A, lift the handle lip 4001, then, pull the staple feeder spring 4002 and pusher 4003 to the back of the tool and disengage, and remove all unused staples to avoid the staples from shooting out when cleaning the jam. The second step, as shown in the FIG. 6B, disassembles the jaw release spring 800. Then, as shown in the FIG. 6C, the right hand holds the control pin 5001; the left hand simultaneously holds the trip lever 600 and takes apart the control pin 5001. Finally, as shown in the FIG. 6D, slip off the front jaw 900 by pivoting it down and off from the back end. Then remove any jammed staples and carefully clean the tool.
This kind of stapler has the hidden danger of staple shooting out when cleaning the jam and on the other hand, it involves several jam cleaning procedure. In addition, the elements were exposed and had much seams, so sand may be deposited at its seams result in its breakdown.
In conclusion, the disadvantages of the prior staplers are as followed:    1. The movement of the driving element of the prior staplers is in a curving way and not in a vertical way. It produces a lateral force besides the vertical force, so that it easily leads to a staple jamming.    2. When cleaning the jammed staples of the prior staplers, the cleaning procedure involves much time, reducing the working efficiency.    3. The prior staplers include many metal elements and many connecting procedures between those elements. Much time and high cost are needed for its production.    4. The prior staplers were limited to use staple of specific size or type, it could not use different size of staples. Due to different factory brand, those staples may have a 5 mm difference in width, causing the staples to jam, even damaging to the tool and seriously injury to the user or others in the work area with the staple fragments.